How does the Nissan GT-R’s Launch Control Work?

The Nissan GT-R’s launch control is iconic in terms of single handedly sending a car into supercar territory. 2.7 seconds is what it takes to propel this car to 60 mph, everyone knows this but there is a lot of confusion about how the GT-R accelerates so quickly. I am prepared to fully crack the code and tell you exactly how the GT-R can keep up the Bugatti Veyron. To fully explain the launch control, I will be explaining each step as they occur in order from activation to flying past 60 mph.

STEP 1: Spooling the Turbochargers

                After activating the launch control, everyone knows that you must press the brake and the accelerator at the same time. This action is needed to spool the turbos to prevent turbo lag. Don't believe me; try launching the GT-R without launch control. No matter what you do you'll reach 60 in around 3.7 to 3.9 seconds with an extremely long initial turbo lag.

Beautiful Engine, but you have to spool those turbos³

STEP 2: Priming the Bilstein DampTronic System

                The Bilstein system is the GT-R’s advanced suspension system that uses dozens of systems that measures vehicle speed, lateral acceleration, torque, engine rpm, and braking behavior to help provide the right amount of dampening. Impressive huh? So of course Nissan would fit in a special protocol for the launch control. Everyone knows that during a sudden acceleration, with or without launch control, the resulting change in inertia causes the weight to transfer to the rear of the car. The weight transfer causes less down force and less grip for the front wheels resulting in torque steer. The resulting wheel spin of the front wheels will extend launches by a few fractions of a second. To prevent such a phenomenon, Nissan tuned the launch system to keep the GT-R flat at launch.  All of this suspension priming occurs as your spooling the turbos in the previous step.

The next 3 steps occur at the same time

STEP 3: Grippy tires, ATTESA E-TS all wheel drive, and VDC = fast times

The next the 3 features of the GT-R that contributes to that amazing acceleration all work at the same time, so I will be combining them in step 3. At this moment, you have just released the brake to start the run.

The stock GT-R wears a set of Dunlop® SP Sport MAXX GT 600 DSST CTT high-performance run-flat tires. To best describe these tires, I would call them street bike tires for cars. That’s not an insult, the level of grip these tires can achieve is unbelievable, and unbelievable grip is needed for launches.

 

Dunlop SP Sport MAXX GT 600 DSST CTT⁴

The advanced total traction engineering system for all-terrain, or ATTESA, is what primarily receives most of the credit for the GT-R’s rapid launches. But if four wheel drive is the magic ingredient then why don't other all wheel drive sports cars with more power like Audis and the new Porsche 991 turbo accelerate to 60 in less than 3 seconds. Obviously there is more to the story than just all wheel drive, but the ATTESA system does play a part in putting all 463lb-ft of torque to the ground. Notice that I said “putting torque to the ground” instead of horsepower, that’s because engine torque is what the tires are subjected to. With ATTESA 50:50 torque distribution each wheel only has to handle 116 ft-lbs of torque, well within the range of what those large Dunlop summer tires can handle. I call it tire efficiency; maximum torque is at or just above what the tires can handle. Something that the BMW M6 and AMG’s need to learn.

The Nissan GT-R’s traction control or Vehicle Dynamic Control (VDC) obviously plays a launches. Because the all-wheel drive system does most of the work by dividing up the torque to manageable levels, the VDC doesn’t have to control a mountain of torque like most super cars with 500+lbs of torque and two wheel drive. Turn off traction control and you will feel a little initial wheel spin so VDC is doing something. But to be able to launch repeatedly and consistently without any hint of wheel spin implies that this dual partnership can achieve big things.

STEP 4: Short gearing goes a long way   

                After those Dunlops hooked up to the pavement, the Nissan GT-R will launch you as if you shot out of a cannon. Before you thinking this step is about the super fast gear shift times, let me inform you that this step is actually about the gear ratios. This is the Nissan GT-R’s biggest secret when it comes to its launch control. The Nissan GT-R has extremely short gears. For those who don't know much about gear ratios let me explain a little bit. When you look at car spec sheets that have gear ratios, you will see numbers associated with each gear. For example, the 2014 Corvette Stingray’s 1^st gear ratio is 2.97:1 which means for every 2.97 revolutions of the engine the transmission’s output drive-shaft performs 1 revolution1. The GT-R’s 1^st gear ratio is 4.56:1; you can see the significant jump in ratios between the two cars2. The higher the ratio numbers the shorter the gear, which means that the engine is able to rev through the gear easier leading to faster accelerations. To put it in simple terms, short gears highlight the engine’s torque and long gears highlight the engine’s horsepower. Sports car companies tend to avoid short gears because even though you’ll accelerate faster, you will achieve a lower top speed. This is why 600hp rally cars with extremely fast acceleration times don’t have high tops speeds to match. Nissan obviously choice to focus on 0-60 mph accelerations so much that they devoted the first 3 gears to be short to achieve the quickest accelerations. Then to try to maintain the high top speed of 198 mph, the GT-R returns to normal size gear ratios. Although they manage to touch 198 mph, it’s also the cause of one the GT-R complaints from hard core performance enthusiasts. For years reviewers have been complaining about how the GT-R flies like a bat out of hell from 0-100 mph, but from 100+ the GT-R becomes gutless. This is because those reviewers are experiencing the transition from short gear ratios to longer gears. Despite the complaints, I believe Nissan have made a good decision.

STEP 5: Now we talk about shift times

2012 Nissan GT-R⁵

                For all of you purest out there who claim that traditional manuals are the way to go and should be available in all sports cars. Let me inform you that the GT-R would not be where it is today if it was equipped with a stick shift. All of the hard work contributed by the systems and hardware explained in the previous four steps would be negated with a traditional manual. Even highly experience racing drivers would not be able to pull fast enough shifts even to maintain a 3 second acceleration time. The driver also has to modulate the clutch to get off the line, another time stripping opportunity. Also, a GT-R with a stick shift manual would mean that every GT-R owner wouldn’t be able to achieve its optimum acceleration time (whatever that would be). Let’s just face the facts; double clutch is the way to go. Not only does it allow every owner to achieve the quickest acceleration runs repeatedly, the 0.15 sec shift times of the double clutch is the final icing on the cake to achieve the mind numbing 2.7 seconds acceleration run.

                Now you are flying past 60 mph, and most likely hitting 80 mph before you realize it. Yes the acceleration is that fast thanks to the above 5 steps. The biggest contributors to the GT-R launch are the all wheel drive system, the short gearing, and the fact that the engine doesn’t produce over 500 ft-lbs of torque (very important for the tire management).  Even though they are the biggest contributors, the entire GT-R package is needed together to create this monster.  The GT-R was not build to have a design presence or to be full of emotion; it was built solely on technology and physics in mind to achieve the fastest 0-60 mph times and to eat up track times. Now you are awed and knowledgeable, which is better than just being awed. 

Resources

1.       Road and Track. "2014 Chevrolet Corvette Stngray Performance Report." Road and Track. RoadandTrack.com, Sept. 2013. Web. 8 Dec. 2013. <http://www.roadandtrack.com/cm/roadandtrack/data/vettecomp.pdf>.

2.       Nissan. "2014 Nissan GT-R Specs." Nissan USA. Nissan, 2013. Web. 26 Nov. 2013. <http://www.nissanusa.com/sportscars/gt-r/versions-specs>.

3.       MotorTrend. "2012 Nissan GT-R Photo Gallery." MotorTrend.com. MotorTrend.com, 29 June 2011. Web. 8 Dec. 2013. <http://www.motortrend.com/photo_gallery/coupes/1105_2012_nissan_gt_r_photo_gallery/photo_06.html>.

4.       Tire Rack. "Dunlop SP Sport Maxx GT 600 DSST CTT." Tire Rack. Tire Rack, n.d. Web. 08 Dec. 2013. <http://www.tirerack.com/tires/tires.jsp?tireMake=Dunlop&tireModel=SP+Sport+Maxx+GT+600+DSST+CTT>.

5.       Hqwide. "Cars Nissan Gtr Wallpaper." HQ Widescreen Wallpapers. Hqwide, n.d. Web. 26 Nov. 2013. <http://hqwide.com/cars-nissan-gtr-wallpaper-40101/>.